Nucleic acids were first extracted from cells in 1869—long before Watson and Crick were born. Explore some of the same techniques used by scientists to determine the chemical composition of nucleic acids back when the contents of cells were unknown. Students isolate DNA then test the extract for components of DNA. Determine if the strands of material isolated from the cells contain deoxyribose, phosphate, and purines using the classic tests—diphenylamine, phosphate, and silver nitrate test for purine.

This kit contains acidic and basic solvents. It should be conducted in a well-ventilated lab with chemical splash goggles, chemical resistant gloves, and aprons. Kit includes reproducible student handouts, detailed teacher notes, and enough materials for fifteen groups of students. A 0.1-g precision balance, ice and boiling water baths are needed.